•
CW beams with Irradiance >~1x10
6
W/cm
2
•
Pulsed beams with Fluence >~1J/cm
2
•
Pulsed beams with Peak power >~1x10
6
W/cm
2
Long-term exposure limits are given in units of time,
and depend primarily on the beam average power and
wavelength. Long-term heating raises the temperature
of the slit and the drum due to exposure to CW or
Pulsed beams with High Average Power in the range
from approximately 10-100W.
Laser damage includes cut or distorted slits, damaged
detectors, damaged power windows, warped optical
encoder and circuit failure, and cut signal cables.
Mechanical damage typically results from dropping the
scanhead, “touching” the slit substrates, operation in
high particulate environments, and repetitive motion.
Mechanical damage includes bent motor shafts,
distorted slits, plugged slits, and broken signal cables.
Out-of-tolerance conditions are either system related,
including problems associated with circuit or motor
failure, or the scanhead is not appropriate for the
application, such as using a Silicon detector to measure
a 1550nm source, or a 25µm slit for a 10µm beam.
Descriptions of the various damage mechanisms and
out-of-tolerance conditions, and guidelines to avoid
such when possible are presented here.
A Nanoscan exposure limit calculator is available from
the web under the Specification tab at:
https://www.ophiropt.com/laser--measurement/beam-profilers/
products/Scanning-Slit-Beam-Profiling-with-NanoScan
Instantaneous damage to slits occurs
due to exposure to:
Slit Aperture Laser Cut Damage
Slit Aperture Laser Burn Damage
